Threaded rebar hoop and method of forming and use thereof

ABSTRACT

Threaded rebar with substantially continuous threads formed using a rolling process, wherein a majority of the circumference of the threaded rebar is covered by discontinuous threads, and wherein no additional steps are required to remove longitudinal ribs in the threaded rebar. The threaded rebar may be used to form threaded rebar hoops that utilize one or more threaded rebar sections and one or more couplings to mechanically couple the ends of the various threaded rebar sections. In such threaded rebar hoops, the external threads are able to engage a coupling, which has internal threads that engage the external threads on the threaded rebar. The mechanically coupled threaded rebar hoops are an improvement over the welded rebar hoops because the mechanically coupled threaded rebar hoops are easier and cheaper to manufacture, ship, and/or install on site, and/or may provide improved strength and/or manufacturability when compared to welded rebar hoops.

CLAIM OF PRIORITY UNDER 35 U.S.C §119

The present Application for a Patent claims priority to ProvisionalApplication No. 62/377,348, entitled “Threaded Rebar Hoop and Method ofForming and Use Thereof,” filed Aug. 19, 2016, and assigned to theassignee hereof and hereby expressly incorporated by reference herein.

FIELD

The present invention is related to the field of threaded rebar, andmore particularly threaded rebar hoops and methods of manufacturing andusing the threaded rebar hoops.

BACKGROUND

Reinforcing metal bars (hereinafter “rebar”) are bars, often made ofsteel, having protruding ribs, which are typically used to reinforceconcrete structures. The protruding ribs can take a number of shapes orgeometries, including diamond shaped, X-shaped, V-shaped, and the like.During the construction of bridges, buildings, and similar structuresthe rebar is often placed in a concrete form and concrete is pouredaround the rebar. The ribs in the rebar help to anchor the rebar withinthe concrete and add strength to the structures in which the rebar isused. In some applications of rebar, such as in columns (for example,columns for bridges, foundations for buildings, or the like), the rebaris formed into a hoop and welded to other rebar structures. In thisregard, the rebar hoops may be tied to or affixed to longitudinallyextending rebar (e.g., vertically or generally vertically rebarextending transverse to the rebar hoops) in order to form the columns.

In typical rebar manufacturing, heated bar stock is fed through rolls toform the cylindrical shaped rebar and protruding ribs. In someapplications the ribs on the rebar can be manufactured and processedafter forming the rebar in the rolls to create threads that extendaround the periphery of the rebar. In one example, rebar may be formed,and after forming the rolled ribs may be machined, grinded, or otherwiseremoved in order to create the threaded ribs. Alternatively, threadedrebar can also be formed by rolling billets using three or more rollers(e.g., non-standard equipment), which does not require subsequentmachining. In some embodiments threads (e.g., machined threaded, notribbed threads formed from rolling) may actually be machined intostandard rolled rebar. However, all of these methods of forming threadedrebar result in increased processing steps and/or non-standard equipmentthat increases the costs of forming threaded rebar products.

Standard rebar and threaded rebar can be manufactured by cold rolling orhot rolling metal billets. In both processes a billet is fed between twocylindrical rolls that form the billet into the rebar. The cylindricalrolls have grooves with notches (e.g., knurls) formed therein to receivea bar and form the core rebar shape and protruding ribs as the barpasses through the rolls. In some rebar manufacturing processes flatdies can replace the cylindrical rolls. The flat dies also have grooveswith notches formed therein, and are spaced apart to receive a bar thatis rotated between them in order to create threads or ribs along thelength of the rebar or a portion thereof.

When threaded rebar is manufactured using cold rolling, the bar ispassed through the rolls at temperatures below the recrystallizationtemperature of the metal, which increases the strength of the metal,improves the surface finish, and results in tighter tolerances on therebar core and threaded ribs. However, cold rolling also causes workhardening of the metal, which results in the metal becoming brittle, andhence, more susceptible to cracking at the base of the formed threadedribs. These cold rolling problems are exacerbated when threaded rebar isused with a coupling, and in these applications the cold rolled threadedrebar is susceptible to premature thread failure. In a hot rollingprocess the bar is passed through the rolls at temperatures above therecrystallization temperature of the metal, which prevents workhardening. Threaded rebar made from hot rolling results in threadedrebar having uniform tensile strength and elongation characteristics, aswell as ribs that are less likely to crack because they are an integralpart of the bar and not work hardened. Furthermore, hot rolling allowsfor the use of steels with higher tensile strength, and hot rollingprocesses do not require additional bar peeling or swaging of thethreaded rebar. However, potential problems with threaded rebarmanufactured through hot rolling include the formation of ribs that arecoarse and that are unable to be used in applications requiring tightthread tolerances.

There are a number of problems associated with manufacturing threadedrebar using cylindrical rolls in a hot rolling process. Cylindricalrolls are used to form square, cylindrical, or other shaped bars intocircular rebar with transverse threads formed into opposite sides of thecircular rebar. The transverse threads formed are discontinuous and insome cases not aligned if the cylindrical rolls are not properlysynchronized. Moreover, in these processes, two longitudinal ribs areformed along the length of the threaded rebar, which is a result of theexcess metal from inconsistencies in the shape of the bar as well as thegap between the cylindrical rolls used to form the threaded rebar. Thegap between the rolls is necessary so that the rolls do not rub againsteach other during the rolling process, since such rubbing may result infrictional heat that could damage the rolling system. The longitudinalribs that result from processing prevent the threaded rebar from beingfreely rotatable within a nut or other mating internally threadedcoupling. In order to manufacture threaded rebar without longitudinalribs, additional steps are necessary that machine or shear off thelongitudinal ribs. In some processes only the longitudinal ribs aremachined off, however, in other processes the entire face of the barwith the longitudinal rib is machined into a flat surface. In stillother processes the longitudinal ribs are sheared off using saw-toothrotary dies, which are spaced apart to shear off sections of thelongitudinal ribs located between the transverse ribs on the threadedrebar. In other processes the longitudinal ribs are ground off using asmooth groove rotary die that grinds down the longitudinal ribs. All ofthese methods present significant drawbacks, including additionalprocessing steps, additional processing time, and additional processingequipment, all of which increase the cost of manufacturing the threadedrebar.

Alternatively, machined threads result in tight tolerances; however,machined threads are weaker than cold rolled threads. Moreover,manufacturing threaded rebar by machining the threads significantlyincreases the manufacturing costs associated with the threaded rebar, asit requires multiple processing steps, as well as being time consumingand resulting in higher handling expenses.

Therefore, there is a need to improve upon the formation of threadedrebar and the products made therefrom.

BRIEF SUMMARY

Embodiments of the present invention address the above needs and/orachieve other advantages by providing systems and methods that are usedto create threaded rebar with substantially continuous threads using arolling process, wherein a majority of the circumference of the threadedrebar is covered by the discontinuous threads; and wherein no additionalsteps are required to remove longitudinal ribs in the threaded rebar.Moreover, the threaded rebar may be used to form threaded rebar hoopsthat utilize one or more threaded rebar sections and one or morecouplings to mechanically couple the ends of the various threaded rebarsections. In such threaded rebar, the external threads are able toengage a coupling (e.g., a nut, collar, or other apparatus), which hasinternal threads that engage the external threads on the threaded rebar.The mechanically coupled threaded rebar hoops are an improvement overthe welded rebar hoops because the mechanically coupled threaded rebarhoops are easier and cheaper to manufacture, ship, and/or install onsite, and/or may provide improved strength and/or manufacturability whencompared to welded rebar hoops or other types of hoops.

Embodiments of the invention comprise a threaded rebar hoop. Thethreaded rebar hoop comprises a threaded rebar having a first end and asecond end, wherein the threaded rebar is formed from a rolling process,wherein the threaded rebar is bent into a hoop shape, and wherein thethreaded rebar is void of longitudinal ribs along at least the first endand the second end of the threaded rebar, and a coupling operativelycoupling the first end and the second end of the threaded rebar to formthe threaded rebar hoop.

In further accord with embodiments of the invention, the threaded rebarhoop comprises a stop operatively coupled to the coupling, the first endof the threaded rebar, or the second end of the threaded rebar.

In other embodiments of the invention, the coupling comprises a stopaperture, wherein the stop is operatively coupled to the stop apertureto reduce or prevent rotation of the coupling on the first end or thesecond end of the threaded rebar.

In still other embodiments of the invention, the coupling comprises analignment feature, wherein the alignment feature is configured foraligning the first end and the second end within the coupling using thealignment feature.

In yet other embodiments of the invention, a first coupling end on thefirst end of the threaded rebar hoop is at least approximately the samelength at the second coupling end on the second end of the threadedrebar hoop.

In further accord with embodiments of the invention, the first end orthe second end has at least a straight portion on which the coupling isoperatively coupled.

In other embodiments of the invention, the threaded rebar is formedwithout longitudinal ribs directly from the hot rolling process.

In still other embodiments of the invention, the hot rolling processcomprises providing a lead pass bar comprising a body extending along alongitudinal axis, wherein at least one portion of the body has across-section defining a plane that intersects the longitudinal axis,wherein a first part of the plane has a first width, a second part ofthe plane has a second width, and a third part of the plane has a thirdwidth, wherein the first width is less than the second width and thethird width, wherein the first part of the plane is located adjacent tothe longitudinal axis, and the second part of the plane and third partof the plane are located distal from the longitudinal axis on oppositeends of the first part of the plane, wherein the lead pass bar has aX-axis through the first part of the plane, the second part of the planeand the third part of the plane, and a Y-axis through only the firstpart of the plane, and wherein the lead pass bar is formed in a firstorientation along the longitudinal axis of the lead pass bar in one ormore lead pass bar roll sets in which the X-axis is substantiallyparallel to and the Y-axis is substantially perpendicular to lead passrolls of the one or more lead pass bar roll sets. The hot rollingprocessing further comprises forming the threaded rebar havingsubstantially continuous threads from the lead pass bar by hot rollingthe lead pass bar in one or more threaded rebar roll sets, whereinforming the threaded rebar comprises forming the threaded rebar from thelead pass bar in a second orientation along the longitudinal axis thatis different from the first orientation in which the X axis issubstantially perpendicular to and the Y-axis is substantially parallelto threaded rolls of the one or more threaded rebar roll sets, andwherein the threaded rebar is formed without having to removelongitudinal ribs along at least a portion of the body.

In yet other embodiments of the invention, the threaded rebar hoop isformed in a shape of a circular hoop, a square hoop, a rectangular hoop,an oval hoop, or a triangular hoop.

In further accord with embodiments of the invention, the threaded rebaris formed from two or more threaded rebar sections having at least onebend and two or more couplings, each of the two or more sections havingthe first end and the second end, wherein the first end of each sectionis operatively coupled the second end of each adjacent section throughthe coupling from the two or more couplings.

In other embodiments of the invention, the rebar has substantiallycontinuous threads.

Another embodiment of the invention comprises a method of forming athreaded rebar hoop. The method comprises forming a threaded rebar froma rolling process, bending the threaded rebar, wherein the threadedrebar has a first end and a second end, and threading a coupling ontothe first end of the threaded rebar hoop. The method further includesdrawing the second end of the threaded rebar hoop adjacent to the firstend of the threaded rebar hoop, and threading the coupling on the secondend of the threaded rebar hoop.

In further accord with embodiments of the invention, the methodcomprises operatively coupling a stop to the coupling, the first end ofthe threaded rebar, or the second end of the threaded rebar.

In other embodiments of the invention, the coupling comprises a stopaperture, and wherein the method further comprises operatively couplingthe stop within the stop aperture to reduce or prevent rotation of thecoupling on the first end or the second end of the threaded rebar.

In still other embodiments of the invention, the rebar hoop comprises analignment feature, wherein the method further comprising aligning thefirst end and the second end within the coupling using the alignmentfeature.

In yet other embodiments of the invention, threading the coupling on thesecond end of the threaded rebar hoop comprises threading the couplinguntil a first coupling end on the first end of the threaded rebar hoopis at least approximately the same length at the second coupling end onthe second end of the threaded rebar hoop.

In further accord with embodiments of the invention, the threaded rebaris formed without longitudinal ribs directly from the hot rollingprocess.

In other embodiments of the invention, the threaded rebar is formed fromtwo or more threaded rebar sections having at least one bend and two ormore couplings, each of the two or more sections having the first endand the second end, wherein the first end of each section is operativelycoupled the second end of each adjacent section through the couplingfrom the two or more couplings.

In still other embodiments of the invention, the rebar has substantiallycontinuous threads.

In yet other embodiments of the invention, forming the threaded rebarcomprises providing a lead pass bar comprising a body extending along alongitudinal axis, wherein at least one portion of the body has across-section defining a plane that intersects the longitudinal axis,wherein a first part of the plane has a first width, a second part ofthe plane has a second width, and a third part of the plane has a thirdwidth, wherein the first width is less than the second width and thethird width, wherein the first part of the plane is located adjacent tothe longitudinal axis, and the second part of the plane and third partof the plane are located distal from the longitudinal axis on oppositeends of the first part of the plane, wherein the lead pass bar has aX-axis through the first part of the plane, the second part of the planeand the third part of the plane, and a Y-axis through only the firstpart of the plane, and wherein the lead pass bar is formed in a firstorientation along the longitudinal axis of the lead pass bar in one ormore lead pass bar roll sets in which the X-axis is substantiallyparallel to and the Y-axis is substantially perpendicular to lead passrolls of the one or more lead pass bar roll sets. Forming the threadedrebar further comprises forming the threaded rebar having substantiallycontinuous threads from the lead pass bar by hot rolling the lead passbar in one or more threaded rebar roll sets, wherein forming thethreaded rebar comprises forming the threaded rebar from the lead passbar in a second orientation along the longitudinal axis that isdifferent from the first orientation in which the X axis issubstantially perpendicular to and the Y-axis is substantially parallelto threaded rolls of the one or more threaded rebar roll sets, andwherein the threaded rebar is formed without having to removelongitudinal ribs along at least a portion of the body.

The features, functions, and advantages that have been discussed may beachieved independently in various embodiments of the present inventionor may be combined in yet other embodiments, further details of whichcan be seen with reference to the following description and drawings.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Having thus described embodiments of the invention in general terms,reference will now be made to the accompanying drawings, wherein:

FIG. 1 provides a top view of a threaded rebar hoop with a singlesection and coupling, in accordance with embodiments of the presentinvention;

FIG. 2 provides a top view of a threaded rebar hoop with multiplesections and couplings, in accordance with embodiments of the presentinvention;

FIG. 3 provides an enlarged view of the threaded rebar hoop couplingillustrated in FIG. 1 or 2, in accordance with embodiments of thepresent invention;

FIG. 4A provides a cross-sectional view of assembling the coupling on afirst end of the threaded rebar hoop, in accordance with one embodimentof the present invention;

FIG. 4B provides a cross-sectional view of the coupling assembled on thefirst end of the threaded rebar hoop, in accordance with one embodimentof the present invention;

FIG. 4C provides a cross-sectional view of the coupling assembled on thefirst end and the second end of the threaded rebar hoop, in accordancewith embodiments of the present invention;

FIG. 5A provides a perspective view of a threaded rebar circular columncage, in accordance with embodiments of the present invention;

FIG. 5B provides a cross-sectional or top view of a threaded rebarcircular column cage, in accordance with embodiments of the presentinvention;

FIG. 5C provides a cross-sectional sectional or top view of a threadedrebar circular column cage, in accordance with embodiments of thepresent invention;

FIG. 6A provides a side view of a threaded rebar square column cage, inaccordance with embodiments of the present invention;

FIG. 6B provides a cross-sectional or top view of a threaded rebarsquare column cage, in accordance with embodiments of the presentinvention;

FIG. 6C provides a cross-sectional sectional or top view of a threadedrebar square column cage, in accordance with embodiments of the presentinvention;

FIG. 7 provides a process flow illustrating the manufacturing process offorming and installing the threaded rebar hoop, in accordance withembodiments of the present invention;

FIG. 8 provides a perspective view of a lead pass rolling system forforming a lead pass bar used to create the threaded rebar, in accordancewith embodiments of the present invention;

FIG. 9 provides a cross-sectional view of the lead pass rolling systemfor forming a lead pass bar used to create the threaded rebar, inaccordance with embodiments of the present invention;

FIG. 10A provides a perspective view of the lead pass bar used to createthe threaded rebar, in accordance with embodiments of the presentinvention;

FIG. 10B provides a cross-sectional view of the lead pass bar used tocreate the threaded rebar, in accordance with embodiments of the presentinvention;

FIG. 11 provides a perspective view of a threaded rebar rolling systemfor forming the threaded rebar from a lead pass bar, in accordance withembodiments of the present invention;

FIG. 12 provides a cross-sectional view of the threaded rebar rollingsystem for forming the threaded rebar from a lead pass bar, inaccordance with embodiments of the present invention;

FIG. 13 provides a perspective view of the threaded rebar formed formthe lead pass bar, in accordance with embodiments of the presentinvention;

FIG. 14 provides a cross-sectional view of the threaded rebar formedfrom the lead pass bar, in accordance with embodiments of the presentinvention; and

FIG. 15 provides a cross-sectional view of rebar formed withlongitudinal ribs.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

Embodiments of the present invention will now be described more fullyhereinafter with reference to the accompanying drawings, in which some,but not all, embodiments of the invention are shown. Indeed, theinvention may be embodied in many different forms and should not beconstrued as limited to the embodiments set forth herein; rather, theseembodiments are provided so that this disclosure will satisfy applicablelegal requirements. Like numbers refer to like elements throughout.

FIGS. 1 through 3 illustrate embodiments of a threaded rebar hoop 1 ofthe present invention. The threaded rebar hoop 1 comprises one or morethreaded rebar sections 3 and one or more couplings 10. The threadedrebar hoop sections 3 comprise a first end 5 and a second end 7. Asillustrated in FIG. 1, in one aspect of the invention the threaded rebarhoop 1 comprises a single section 3 having a first end 5 and a secondend 7, and wherein the first end 5 is operatively coupled to the secondend 7 through the use of a coupling 10, as will be described in furtherdetail with respect to FIGS. 4 through 7. In other aspects of theinvention the threaded rebar hoop 1 comprises two or more sections 3,such as a first section 30, a second section 32, and third section 34 asillustrated in FIG. 2. As illustrated in FIG. 2, a first end 5 of thefirst section 30 is operatively coupled to a second end 7 of the secondsection 32; a first end 5 of the second section 32 is operativelycoupled to a second end 7 of the third section 34; and a first end 5 ofthe third section 34 is operatively coupled to a second end 7 of thefirst section 30.

FIG. 3 illustrates an enlarged view of the coupling 10 and theconnection between the first end 5 and second end 7 of a threaded rebarsection 3, while FIG. 4 illustrates a cross-sectional view of assemblingthe coupling. It should be understood that the coupling has a firstportion 12 that is operatively coupled to the first end 5 of a threadedrebar section, and a second portion 14 that is operatively coupled to asecond end 7 of a threaded rebar section, as will be discussed infurther detail below. Moreover, the coupling comprises an internalcavity 16 there through in which the first end 5 and second end 7 of thethreaded rebar section 3 is installed when assembled into a threadedrebar hoop 1. It should be understood that the internal cavity 16 of thecoupling 10 has threads 18 that are configured to mate with the threads9 on the surface of the threaded rebar sections 3 to operatively couplethe first end 5 and second end 7 of the one or more threaded rebarsections 3 together. In some embodiments the internal cavity 16 is anenclosed cavity; however, in other embodiments the cavity may bepartially open (e.g., an opening in a portion of the coupling, anopening extending along the length of the coupling, such as a slot, orthe like).

It should be understood that as illustrated in FIGS. 1 and 2, the sizeof the threaded rebar hoops 1 may vary based on the needs of thecustomer. For example, the threaded rebar hoops 1 may be of a size thatallows for the formation of a threaded rebar hoop 1 using a singlethreaded rebar section 3 as illustrated in FIG. 1. However, asillustrated in FIG. 4 multiple threaded rebar sections 3 may be used toform larger threaded rebar hoops 1. For example, the threaded rebarhoops may be 6, 8, 10 12, 14, 16, 18, 20, or more feet in diameter (orany size less then, between, or greater than these sizes) and as suchmay require multiple threaded rebar sections 3 to form threaded rebarhoops 1 having these sizes. Furthermore, it should be understood thatexisting rebar hoops are typically shipped to a customer in aconfiguration in which they have already been assembled, since theassembly is often of a permanent nature, such as a welded configuration.As will be described in further detail later, since the threaded rebarhoops 1 of the present invention may be formed through the use ofmultiple threaded rebar sections 3, the threaded rebar sections 3 may beshipped in a bundle and assembled on site using couplings 10 to reduceshipping costs associated with shipping assembled threaded rebar hoops1.

It should be further understood that the shape of the threaded rebarhoops 1 in FIGS. 1 through 3 are illustrated as circular hoops. However,in the construction industry rebar hoop also describes shapes other thancircular, such as rectangular, square, oval, or other like shape. Assuch, as described with respect to FIGS. 1 and 2, like the circular hoopshapes, these other shapes may have two or more sections that arecoupled together through the use of two or more couplings 10.

It should be understood that the threaded rebar hoops 1 illustratedherein, specifically the circular threaded rebar hoops 1, may have aportion at the ends 5, 7 that is straight (e.g., not bent with a radiusof curvature). Depending on the size of the threaded rebar hoops 1, thesize of the couplings 10 (e.g., the length of the couplings 10), and thedistance of travel of the couplings 10 along the threaded rebar sections3 during assembly, the threaded rebar hoop ends 5, 7 may not be requiredto have a portion that is straight. In these cases the coupling 10 issized for tolerances that would allow it to be coupled to slightly bentends 5, 7 of the threaded rebar hoop 1. However, it is likely that atleast a portion of the ends 5, 7 will not be bent so as to allow thecouplings 10 to operatively couple the ends 5, 7 between one or moresections 3 of the threaded rebar hoop 1 together.

FIGS. 4A through 4C illustrate assembling a first end 5 and second end 7of one or more threaded rebar sections 3 of a threaded rebar hoop 1,while FIGS. 5A-6C illustrate different rebar hoops installed in rebarcages 500, 600. FIG. 7 illustrates a process flow for assembling athreaded rebar hoop 1 and installing it in a rebar cage 100. Asillustrated by block 102 in FIG. 7, a threaded rebar is formed, whichmay be used as a threaded rebar section 3, or which may be cut into athreaded rebar section 3. In some aspects of the invention the threadedrebar is formed from a rolling process, such as a cold rolling processor hot rolling process. In other embodiments of the invention, thethreaded rebar product may be formed without longitudinal ribs extendingalong at least a portion of the first 5 end and/or second end 7 of thethreaded rebar, or the entire length of the threaded rebar product. Insome aspects of the invention the threaded rebar is formed by rolling alead pass bar, rotating the lead pass bar, and rolling the lead pass barinto the threaded rebar, as will be discussed in further detail laterwith respect to FIGS. 8 through 15. However, it should be understoodthat the threaded rebar product may be formed through any type offorming process including, but not limited to, rolling the threadedrebar product and machining the longitudinal ribs off of the threadedbar after rolling, rolling the threaded rebar using three or morerollers (non-standard rolling equipment), rolling the threaded rebarproduct using rolling sets that are offset 90 degrees (e.g., a lead passrolling set and a threaded roll set that is rotated 90 degrees from thelead pass rolling set).

Block 104 of FIG. 7 illustrates that the one or more threaded rebarsections 3 are bent into an arc. In some aspects of the invention, asingle threaded rebar section 3 is used to create the threaded rebarhoop 1, and as such the threaded rebar section 3 is bent into a circularhoop shape, as illustrated in FIG. 1. In other aspects of the invention,two or more threaded rebar sections 3 are bent into arced shapes, suchas two half circle sections, or other arced shapes based on the size ofthe threaded rebar hoop 1 and the number of sections 3 being used. Forexample, as illustrated in FIG. 2 there is a single half circle section30, and two quarter circle sections 32, 34, which are all bent or curvedto form the desired circular threaded rebar hoop 1. In other embodimentsof the invention the two or more sections of the rebar hoop 1 may beequal. It should be understood that although the rebar hoops 1 areillustrated as being generally circular, the threaded rebar sections 3may be bent into any shape in order to form a threaded rebar hoop 1 ofany contour or shape, such as but not limited circular, oval, square,rectangular, triangular, polygonal, any non-uniform shape, or any othercurvilinear shape.

FIG. 7 further illustrates in block 106 that a coupling 10 is threadedonto the first end 5 of a threaded rebar section 3. In one example ofblock 106, FIGS. 4A and 4B illustrate that a coupling 10 is rotated ontothe first end 5 of a threaded rebar section 3. Block 108 of FIG. 7illustrates drawing (e.g., pulling or otherwise moving) the second end 7of the threaded rebar section 3 adjacent the first end 5 of the threadedrebar section 3, as illustrated in FIG. 4B. In some aspects of theinvention the ends of the threaded rebar section(s) 3 may touch, whilein other aspects of the invention the ends of the threaded rebarsection(s) 3 may have a gap between them as they are operatively coupledusing the coupling 10.

FIG. 7 further illustrates in block 110, that the coupling 10 ispartially unthreaded off of the first end 5 of the threaded rebarsection 3 to at least partially on the second end 7 of the threadedrebar section 3, as illustrated by FIG. 4C. In some aspects of theinvention, this includes threading the coupling 10 onto the second end7, such that a first portion 12 of the coupling 10 is located around thefirst end 5 of the threaded rebar section 3, while a second portion 14of the coupling 10 is located around the second end 7 of the threadedrebar section 3. It should be understood that the rebar hoop 1 myinclude an alignment feature, which may include a viewing aperture 40 inthe coupling, a marking feature on the threaded rebar section 3, or thelike. It should be understood that the coupling 10 may have one or moreviewing apertures 40 (e.g., hole, slot, void, window, notch within or atan edge of the coupling) that allows a user during assembly to view thelocation of the first end 5 and/or second end 7 within the coupling 10in order to determine if the coupling 10 is positioned correctly on thefirst end 5 and second end 7 of the threaded rebar hoop 1. That is, toallow a user to determine that the first end 5 and second 7 of thethreaded rebar section(s) 3 meet at least generally in the middle of thecoupling 10. For example, the first portion 12 of the coupling 10 coversa length of the first end 5 of the threaded rebar section that isgenerally the same length as the second end 7 of the threaded rebarsection that is covered by the second portion 14 of the coupling 10. Inother embodiments of the invention the threaded rebar section(s) 3 maybe marked (e.g., colored, embossed, notched, or the like) to illustratethe location to which the coupling 10 should be assembled. For example,portions of the threaded rebar 3 may be marked on the first end 5 andthe second end 7, such that when assembled both markings on the threadedrebar 3 may be seen on either side of the coupling 10.

Block 112 of FIG. 7 further illustrates that one or more stops 50 areoperatively coupled to the threaded rebar first end 5, the threadedrebar second end 7, and/or the coupling 10 to reduce or prevent movementof the coupling 10 (i.e., there may be small movement and/or rotation ofthe coupling 10). In some aspects of the invention, as illustrated inFIGS. 3 through 4C, the one or more viewing apertures 40 may also be theone or more stop apertures 42 through which a stop 50 is used to reduceor prevent movement of the coupling 10. However, it should be understoodthat the one or more viewing apertures 40 may be different from the oneor more stop apertures 42 (e.g., hole, slot, void, window, notch withinor at an edge of the coupling). As illustrated in FIG. 4C, at least aportion of the stop 50 may be located between the first end 5 and thesecond end 7 within the cavity 16 of the coupling 10. In someembodiments the stop 50 may extend from a first stop aperture throughthe cavity 16 of the coupling 50 and into a second stop aperture. Thestop 50 is illustrated as being located through the coupling; however,it should be understood that the stop 50 may be located at the end ofthe first portion 12 or the end of the second portion 14 of the coupling10. As such, in some embodiments of the invention the stop may notextend into or through the cavity 16 of the coupling 10. For example,the stop may be operatively coupled to the threaded rebar sections thatare exposed outside of the coupling 10 (e.g., inserted into an aperturein the threaded rebar, coupled to the external surface of the threadedrebar, or the like apart from the coupling 10). The stop 50 may be anytype of feature, such as but not limited to a fastener (e.g., screw,bolt, pin, or the like), a wire, flange, collar, clamp, lever, or anyother like feature that prevents or limits the movement of the coupling10 once assembled.

The stop 50 may be utilized to not only reduce or prevent movement ofthe coupling 10 during installation on site, but also duringtransportation, during which the vibrations from the transport couldpotentially cause the coupling 10 to rotate off (e.g., back-off, or thelike) the first end 5 and/or second end 7 of the threaded rebar section3. In some embodiments, the stop 50 is a self-drilling, self-threadingand/or self-tapping fastener (e.g., screw, or the like), such that thefastener may form threads within the stop aperture 42 during assembly,in order to reduce or prevent the stop 50 from backing out of the stopaperture 42.

Block 114 of FIG. 7 further illustrates that one or more threaded rebarhoops 1 may be shipped to a site for use within a construction product,such as a support column within a bridge, other like support structure.As such, it should be understood that the threaded rebar hoop 1 may besent to its destination for installation in the assembled form, in whichit can be used along with other threaded rebar, or other types of rebar,for creating a rebar cage for concrete fill for supporting a structure.Alternatively, instead of shipping the threaded rebar hoop 1 in itsassembled form, the one or more rebar sections 3 may be delivereduncoupled (e.g., bundled together, or the like), such that the threadedrebar hoops 1 may be assembled on site during installation of a rebarcage. By not having to weld rebar to make a hoop, the coupling of therebar sections 3 may be done on site using the coupling 10, and thuspotentially hazardous and time consuming welding processes are notrequired to be performed on site or before shipping to the site.Moreover, by installing the threaded rebar hoops 1 on site, theinstallation process may be sped up and/or improved because of theflexibility of the threaded rebar sections 3 before they are formed intoa hoop may ease the assembly of the rebar cage. For instance, withrespect to welded hoops, the hoops are typically rigid and operativelycoupling (e.g., tying) the hoops to transverse rebar (e.g., verticalrebar within a column, or the like) may be difficult and time consuming.Unlike the welded hoops the uncoupled threaded rebar hoops 1 are moreeasily manipulated before the coupling 10 is used to create the threadedrebar hoop 1. Moreover, pre-welded hoops may have tolerance issuesbecause the pre-welded hoops are shipped to a construction site andmight not fit properly in the rebar cage. Alternatively, the couplings10 allow for tolerance differences in the rebar cage because thecouplings 10 allow for slight adjustments in the sizes of the rebarhoops 3. For example, the distances between the ends of the sections maybe spaced apart or brought closer together to account for tolerancedifferences. Welded rebar hoops do not allow for the slight adjustments(e.g., in welded applications the ends of the hoops have to be weldedtogether, and thus the size of the rebar hoop is static).

It should be further understood that performing a welded connectionbetween ends of rebar may be a difficult process to repeat, and thus,the strength of welded rebar hoops are dependent on the strength of thewelds. As such, welded rebar hoops may require destructive testing byengineers, construction entities, or regulators before they can beutilized within a project. In some cases, 20 percent (or more or lessdepending on regulations) of the welded hoops may be required to undergodestructive testing in order to satisfy safety requirements forconstruction products, and thus, the threaded rebar undergoingdestructive testing is useless for the construction product, which addsadditional costs to the project. The threaded rebar hoops 1 of thepresent invention may provide improved strength and/or improvedrepeatability of the strength of the hoop at the coupling location, suchthat the destructive testing of the threaded rebar hoop 1 is notrequired, or at least the amount of testing may be reduced. As such, theimproved strength and/or improved repeatability of the strength at thecoupling location reduces the costs associated with the constructionproject.

It should be understood that the threaded rebar hoop 1 of the presentinvention may have improved strength of 1, 2, 3, 4, 5, 6, 7, 8, 9, 10,15, 20, 25, 30, 35, 40, 45, 50, 70, 90, 100, 125, 150, 175, 200, 300,400, 500, 600, 700, 800, 900, 1000, or more percent (or any range ofpercent improvement that falls within, overlaps, or is outside of thesevalues) when compared to welded hoops.

FIGS. 5A and 6A illustrates views of rebar columns 500, 600, in someembodiments of the present invention. Moreover, FIGS. 5B and 5C, and 6Band 6C illustrate different cross-sectional views and/or top views ofthreaded rebar cage columns. FIGS. 5B and 6B illustrate rebar cages inwhich the rebar hoops 1 are located on the outside of the longitudinalbars 500, 600, while FIGS. 5C and 6C illustrate rebar hoops 1 locatedboth outside and inside of the longitudinal bars 500, 600. FIGS. 5A-5Cillustrate a circular column rebar cage 400 that utilizes circular rebarhoops 1, while FIGS. 6A-6C illustrate a square column rebar cage 500that utilizes square rebar hoops 1. However, it should be understoodthat any type of column rebar cage, non-uniform rebar cage, or the likemay incorporate different rebar hoops 1 of different shapes and sizes.

It should be understood that typical rebar cage column construction mayinclude operatively coupling longitudinal bars to the welded rebarhoops. The welded rebar hoops may be tied or welded to the outsideand/or inside of longitudinal bars (e.g., vertical bars in the columns)of the rebar cage. The rebar cage columns may be formed on the groundand hoisted into place. For example, the hoops may be placed in framesand the longitudinal bars may be attached thereto. In some embodimentsthe rebar cages are formed in facilities and transported on site to behoisted into place. In other embodiments the rebar hoops may be added tothe structure as it is being built in the installed position. It shouldbe understood that if the rebar hoops are not properly secured to thelongitudinal bars the strength of the rebar cage could be greatlyreduced before it is encapsulated in concrete, and thus portions of therebar cage could fail and/or deform (e.g., which could cause structuralproblems if not identified before the concreate is added).

As previously discussed the threaded rebar hoops 1 of the presentdisclosure not only result in improved strength, but the rebar hoops mayallow for improved installation processes that reduce costs. As such,the rebar hoops 1 may be used in the same way as welded rebar hoops(e.g., cages built at the factory or built on site, and hoisted intoplace), or the rebar hoops 1 of the present invention may partially orcompletely replace the welded rebar hoops 1. The rebar hoops 1 of thepresent disclosure may also be particularly useful when installing therebar cages in place. For example, as the longitudinal rebar 502, 602 isbeing installed in the columns, the rebar hoops 1 may be placed aroundthe longitudinal rebar 502, 602 at the desired locations. Moreover,regardless of the number of sections 3 used in the threaded rebar hoop 1(e.g., one, two, three, or the like) the present invention may allow foradjusting the size of the hoops by making the ends of the sections 3closer together and/or farther apart as the multiple sections are beingassembled (e.g., in the rebar cage in the installed position, as apre-assembly on site or at a manufacturing facility). In some cases,when installing the rebar hoops 1 on the outside of the longitudinalbars of a rebar cage column the ends of the rebar hoops 1 may be pulledtogether to provide a tighter fit around the longitudinal bars.Alternatively, when installing the rebar hoops 1 within the longitudinalrebar of the rebar cage, the ends of the sections 3 may be spaced apart(e.g., moved away from each other) when the one or more couplings 10 areused to provide a tighter fit within the rebar cage.

With respect to threaded rebar hoops having two or more sections 3 andtwo or more couplings 10, utilizing multiple sections 3 and assemblingthe rebar cages on site reduces shipping costs because the sections 3may be bundled and shipped in smaller spaces and/or packages. Theimproved shipping costs may be especially true for large support columnsfor buildings and bridges, which may require oversized rebar hoops thatmay be difficult to transport to the construction site due to the limitsof road clearances, and/or may be required to be assembled in theinstalled position because the pre-assembled columns may be not be ableto be lifted into place. As such, in this way the threaded rebarsections 3 may be transported to the site in the bundles and assembledusing couplings 10, and thereafter tied and/or welded to longitudinalbars.

While FIGS. 5A-6C illustrate perspective and top view of circular andsquare column rebar cages 500, 600, it should be understood thatdifferent shapes of the column rebar cages (e.g., rectangular, oval, orthe like) may be formed using the threaded rebar hoops 1. Moreover, thecombinations of rebar hoops 1 may be used in any type of rebar cage,such as wind tower bases, bridge floors, or other structural ornon-structural components of any type of structure.

Moreover, not only may the couplings 10 described herein be utilizedwith the rebar hoops 1 of the rebar cages, but the couplings 10 may alsobe utilized to operatively couple the longitudinal bars of the rebarcages together and/or to operatively couple other portions of the rebarcages together, where one end of a first threaded rebar meets anotherend of a threaded rebar. As such, the couplings 10 and/or the rebarhoops 1 described herein may be utilized in combination with other rebarcage elements to create a rebar cage system that is cheaper tomanufacture (e.g., through the threaded rebar forming process describedbelow), cheaper to ship (e.g., components may be more easily bundled andshipped), stronger (e.g., the couplings 10 provide a more reliablestrength determination over the plurality of rebar hoops), cheaper andfaster to assemble (e.g., less destructive testing is needed, can bemore quickly installed, and because it is stronger less rebar hoops 1are need because they can be spaced farther apart), and/or more flexibleinstallation (e.g., the rebar hoops 1 can be assembled as the structureis being built instead of pre-assembled).

With respect to forming the threaded rebar sections 3 described herein,the threaded rebar sections 3 may be formed by first rolling (e.g., coldrolling or hot rolling) a billet 200 into a lead pass bar 220, rotatingthe lead pass bar 220 to a different orientation, and rolling the leadpass bar 220 into the threaded rebar 240, as illustrated in FIGS. 8-14.The lead pass bar 220 may have a cross-section with upper and lowerwidth dimensions (see A in FIG. 10B) and a reduced dimension (see B inFIG. 10B) approximate the center of the lead pass bar 22 that is lessthan the upper and lower width dimensions. In one embodiment of theinvention, the billet 200 can be formed into a lead pass bar 240 with across-section in the shape of an hourglass (i.e., the hourglass/peanutshaped lead pass bar depicted in FIGS. 10A and 10B) by feeding thebillet through a first set of rolls (i.e., lead pass roll set 300) thatforms the hourglass shape. As explained in further detail below thehourglass cross-section aids in the production of a substantiallycontinuous threaded rebar 240 with little to no longitudinal ribs 262,which is used to create the threaded rebar sections 3 described above.After the lead pass bar 200 is formed it is passed through a second setof rolls (i.e., threaded pass roll set 350) in order to form thesubstantially continuous threaded rebar 240 with little to nolongitudinal ribs 262. The billet 200, the lead pass bar 220, and thethreaded rebar 240 are typically processed consecutively at the samemill, however, it is understood that in some embodiments they may beprocessed at different mill sites.

In the present invention, the threaded rebar sections 3 can be producedusing conventional rebar processing equipment and without the additionalsteps and tooling that are used for removal of the longitudinal ribs262. Therefore, it is generally not necessary to use more than two rollsor more than two dies at a time to create the substantially continuousthreaded rebar 240, or to use little to no additional machining,grinding, or shearing operations to remove a portion of the longitudinalribs 262. The present invention results in threaded rebar 240 that canbe used to create the threaded rebar sections 3 for the threaded rebarhoops 1 described herein utilizing standard rebar manufacturing toolingand equipment in less time and for less cost than conventional threadedrebar products made utilizing more complex manufacturing processes andequipment.

It should be understood that after the cross-sectional area of thebillet 200 is reduced to the proper size, the hot roll lead pass rolls300 shapes the billet 200 into a lead pass bar 220 with the propercross-sectional area for producing a threaded rebar product withoutlongitudinal ribs. The type of cross-sectional area of the lead pass bar200 will impact the surface quality and circular cross-section of thefinal threaded rebar 240. If a lead pass bar 220 with the propercross-sectional area is not used, excess material can build up betweenthe gaps in the rolls and create longitudinal ribs 262 in the threadedrebar 240, as illustrated by the rebar product 260 in FIG. 15.

In order to create threaded rebar 240 with little to no longitudinalribs 262, a bar with a reduced width (see B of FIG. 10B) along orapproximate to the y-axis is helpful in reducing or eliminating thematerial that spreads into the gaps between the rolls. The greater thewidth of the cross-sectional area along the y-axis of the lead pass bar220 the larger the longitudinal ribs 262 might be along the length ofthe threaded rebar 240. A longitudinal rib 262 prevents the threadedrebar 240 from being used in conjunction with a coupling 10 or othertype of mating threaded part 24 because the longitudinal ribs 262prevent the threaded rebar 240 from turning within the coupling 10 orother mating part.

It should be understood that typical threaded rebar 260 that includeslongitudinal ribs 262, as illustrated in FIG. 15, requires additionalstages of manufacturing to machine, file, shear, chip, or otherwiseremove the longitudinal ribs 262 in order to allow the threaded rebar tobe used with a threaded coupling. These additional process steps addincreased tooling, man-hours, manufacturing time, and floor space coststhat ultimately increase the overall cost of manufacturing typicalthreaded rebar 260. Alternatively, not having enough cross-sectionalmaterial along the y-axis of the lead pass bar 220 prevents theformation of a circular threaded rebar with threads that span themajority of the circumference of the threaded rebar 240 because thematerial will not properly flow into the grooves and knurls in theopposing rolls. This can lead to a threaded rebar product with lesstensile holding strength, weakened threaded rebar that is more apt tofail, deformed threaded rebar that cannot be secured to a coupling, etc.Therefore, it is important to create a lead pass bar 220 with across-sectional area that results in a threaded rebar 240 product havingthe proper shape for tensile strength, but with little to nolongitudinal ribs 262.

The dimensions and shape of the cross-sectional area of the lead passbar 220 play a role in producing threaded rebar 240 with little to nolongitudinal ribs 262. FIGS. 10A and 10B illustrate one embodiment of alead pass bar that has an hourglass or peanut shaped cross-section. Thelead pass bar 220 has a body extending along a longitudinal z-axis. Atleast a portion of the body has a cross-section defining a plane 222 inthe vertical x-axis and horizontal y-axis that intersects thelongitudinal z-axis as illustrated in 10A. The first part 224 of theplane 222 has a first width (see A) and the second part 226 of the plane222 has a second width (see B) that is different than the first width ofthe first part 224. In other embodiments of the invention, the plane 222has a height dimension (see C) substantially centered along thelongitudinal z-axis. The first part 224 of the plane 222 is locatedvertically adjacent to the longitudinal z-axis and the first width issmaller than the second width of the second part 226 of the plane 222located vertically distal from the longitudinal z-axis. In otherembodiments of the invention, the first part 224 of the plane 222 isvertically adjacent to the longitudinal z-axis and the first width issmaller than the second width of the second part 226 of the plane 222,and the third width of the third part 228 of the plane 222, wherein thesecond part 226 of the plane 222 and third part 228 of the plane 222 arelocated vertically distal from the longitudinal z-axis. In someembodiments, the first part 224 of the plane 222 is rectangular in shape(see D) and the second part 226 of the plane 222 and third part 228 ofthe plane 222 are at least approximately circular, wherein the secondpart 226 of the plane 222 is located vertically above the first part 224of the plane 222 and the third part 228 of the plane 222 is locatedvertically below the first part 224 of the plane 222. In otherembodiments of the invention, the x-axis may be in the horizontalposition and the y-axis may be in the vertical position dependent on theposition of the lead pass bar 222.

As previously discussed the shape of the lead pass bar 220 illustratedin FIGS. 10A and 10B may be described as having an hourglass and/orpeanut shape. These shape descriptions may only generally describe theshape that the lead pass bar 220 may take in a given embodiment. Forexample, a traditional peanut or hourglass shape has circular opposedends connected by a vertical shaft. In general terms, the lead pass bar222 of various embodiments has two opposed ends with a wider dimensionthan a central connecting section that generally resembles a peanut orhourglass, but the lead pass bar does not have to necessarily includecircular opposed ends and a flat vertical connecting section. Forexample, in some embodiments of the invention, the lead pass bar 222 mayhave flat sections in the first part 224 of the plane 222 (see D), asillustrated in FIGS. 10A and 10B. However, in other embodiments of theinvention the flat sections may have a curved surface with an associatedradius of curvature (e.g., convex or concave). In still otherembodiments of the invention, the flat sections may have a v-shape orhave another shape that provides a reduced cross-sectional area along ornear the y-axis (i.e., mid-section of the lead pass bar) illustrated inFIGS. 10A and 10B.

In the embodiment illustrated in FIGS. 10A and 10B the lead pass bar 220has rounded top edges and bottom edges. In some embodiments of theinvention, the top edge and bottom edge of the lead pass bar 220 are arectangular shape. In other embodiments the top edge and bottom edge canhave various shapes and the shape of the lead pass bar 220 may only needto be a reduced width (e.g., the first width) that runs approximate tothe y-axis of the cross-sectional area for at least a part of the lengthof the longitudinal z-axis of the body of the lead pass bar 220. In someembodiments, the shape of the lead pass bar 220 may be hyperbolic,notched, or have some other type of geometry that has a reducedcross-sectional area in the midsection (i.e. y-plane or near they-plane) of the bar.

In order to create the hourglass lead pass bar 220, the rectangularbillet 200 is fed through a lead pass roll system 300 that has opposingrolls, as illustrated in FIGS. 8 and 9. As an aid to understanding thefigures, FIG. 9 illustrates the gap between the opposing lead passrollers 302 and 304. In one embodiment of the invention the lead passroll system 300 comprises a first lead pass roll 302 and a second leadpass roll 304 (collectively the “lead pass roll set”), a transmission306, and a bar guide 308. The first lead pass roll 302 and the secondlead pass roll 304, have grooves 310 machined or formed in the shape ofhalf of the hourglass lead pass bar 220 (e.g., if the lead pass bar wascut along the x-axis). The grooves 310 and roll surfaces 312 define theshape of the lead pass bar.

The rectangular billet 200 as illustrated in FIG. 9, is fed into the hotrolled lead pass system 300 in an orientation where the x-axis of thelead pass bar lies horizontal and the y-axis of the lead pass bar is inthe vertical direction with respect to the first lead pass roll 302 andsecond lead pass roll 304. The transmission 306 drives the first leadpass roll 302 in a counter-clockwise direction, while driving the secondlead pass roll 304 in a clockwise direction. In this way, the lead passbar 220 will exit the rolls, and thus the bar guide 308, with the x-axisin the horizontal direction and the y-axis in the vertical direction, asillustrated in FIG. 8.

A threaded pass roll system 350, which has two opposing rolls, is usedin order to manufacture the threaded rebar 240, as illustrated in FIGS.11 and 12. As illustrated in FIG. 11, in one embodiment of theinvention, the threaded pass roll system 350 comprises a first threadedpass roll 352 and a second threaded pass roll 354 (collectively the“threaded pass roll set”), a transmission 356, and bar guide 358. Thefirst threaded pass roll 352 and the second threaded pass roll 354, asillustrated in FIG. 11, have grooves 360 and knurls 362 machined orformed in the shape of a semi-circle. As illustrated in FIG. 12, thelead pass bar 220 is fed through the hot rolled threaded pass system 350in order to produce the threaded rebar 240 product. The lead pass bar220 as illustrated in FIG. 12 is fed into the hot rolled threaded passsystem 350 in an orientation where the x-axis is in the verticaldirection and the y-axis is in the horizontal direction with respect tothe first threaded roll 352 and second threaded roll 354. Thetransmission drives the first threaded roll 352 in a counter-clockwisedirection, while driving the second threaded roll 354 in a clockwisedirection. In this way, the substantially continuous threaded rebar 240will exit the rolls and the bar guide 358, with the x-axis in thevertical direction and the y-axis in the horizontal direction, asillustrated in FIG. 11. It is important to note that, unlike otherthreaded rebar processes, little to no additional machining or formingsteps are necessary after the threaded rebar 240 exits the threadedrebar pass to remove longitudinal ribs 262, due to the fact that thethreaded rebar 240 has little to no longitudinal ribs 262 along at leasta portion of the length of the threaded rebar 240. In some embodiments,the threaded rebar 240 that is produced after the hot rolled threadedrebar pass need only be cooled, bent into the desired threaded rebarsections 3, and/or coupled together using the coupling 10, as describedabove, before it is shipped to the customer (or shipped to the customerthen assembled).

FIG. 13 illustrates one embodiment of the threaded rebar 240. Asillustrated in FIG. 13, the top threads 242 are formed by the firstthreaded pass roll 352 and the bottom threads 244 are formed by thesecond threaded pass roll 354. It is important that the top threads 242are substantially lined up with the bottom threads 244 in order for thethreaded rebar 240 to work properly within various applications (e.g.,be able to mate with a coupling, etc.). In some embodiments, the firstthreaded roll 352 and the second threaded roll 354 may have to beproperly aligned with each other so the knurls 362 of each roll producetop threads 242 and bottom threads 244 that are substantially alignedwith each other.

As illustrated in FIGS. 13 and 14 the alignment of the top threads 242and the bottom threads 244 produce a discontinuous threaded rebar 240.However, a single discontinuous thread covers substantially the entirecircumference of the threaded rebar 240 thereby creating a substantiallycontinuous thread. In some embodiments of the invention a singlesubstantially continuous thread, made up of a top thread 242 and bottomthread 244, can span over ninety (90) percent (or more or less, such as60, 65, 70, 75, 80, 85, 95, or the like percent, or within a range ofany of the forgoing) of the circumference of the threaded rebar 240. Thecircumference of the threaded rebar 240 that the substantiallycontinuous threads cover may be changed by altering the dimensions ofthe knurls 362 in the grooves 360 of the first threaded roll 352 andsecond threaded roll 354.

Another feature of the threaded rebar 240 produced using this lead passbar 220 is that there are little to no longitudinal ribs 262 that runalong the surface of the threaded rebar 240 in the longitudinaldirection, or at least along a partial length of the threaded rebar 240.As illustrated in FIG. 15, typical threaded rebar 260 manufactured usinga rolling process has a cross section with pronounced longitudinal ribs262 that run the length of or at least a portion of the body of typicalthreaded rebar 260. The longitudinal ribs 262 are due to the excessmaterial that fills the gaps 370 between the first threaded roll 352 andthe second threaded roll 354, as illustrated in FIG. 12. In a typicalthreaded rebar manufacturing process, these pronounced longitudinal ribs262 are of sufficient dimension so as to obstruct threading a couplingonto the threaded rebar without subsequent post-forming machining,grinding, shearing, etc. of the longitudinal ribs 262 of the threadedrebar. In the embodiments of the present invention where a little orslight longitudinal rib may exist on the threaded rebar 240, the littleor slight longitudinal rib is not of sufficient dimension so as toobstruct threading a coupling onto the threaded rebar. Moreover, in theembodiments when the area of the longitudinal ribs are slightly concave,the slightly concave shape does not have an effect on the couplings. Assuch, when the area of the longitudinal ribs are slightly concave orconvex, the threaded rebar will still be considered to have nolongitudinal ribs as long as the coupling is able to be threaded on thebar without having to perform additional manufacturing on area of thelongitudinal ribs. Therefore, subsequent post-forming machining,grinding, shearing, etc. of the longitudinal ribs of the threaded rebaris not necessary.

Along with the dimensions of the lead pass bar 220, the gap distance(see G), may also play an important role in preventing longitudinal ribsfrom forming along the length of the threaded rebar 240. The shape ofthe lead pass bar 220, as well as the gap distance, helps to prevent themetal from filling the gaps 370 between the first threaded roll 352 andthe second threaded roll 354, thus preventing longitudinal ribs 262 fromforming in the present invention. If the gap is too small, material mayfill the gap and form longitudinal ribs 262, or alternatively, if thegap is too large the threaded rebar 240 may not form the propercylindrically shaped core or threads.

As illustrated by FIGS. 13 and 14, the threads 242, 244 may besubstantially continuous. Furthermore, the outer circumference of thethreads may provide a circular or substantially circular cross-section,such that if a line was extended around the outer circumference of thethreads 242, 244, the outer circumference may be circular orsubstantially circular, as illustrated by the thread diameter TD.Additionally, the core of the threaded rebar 240 may also be circular orsubstantially circular, as illustrated by the core diameter CD. Asillustrated by FIG. 14 there are material voids 246 where there is alack of metal material in the outer edges of the threaded rebar 240. Thematerial voids 246 create the appearance that the threaded rebar 240 isnot circular or substantially circular, however, as discussed the topthreads 242 and bottom threads 244 have a diameter TD that is circularor substantially circular and will mate with a circular or substantiallycircular coupling 10.

Different types of threaded rebar 240 can be produced by simply changingthe dimensions of the grooves 310, 360 and knurls 362 in the lead passrolls 302, 304 and threaded pass rolls 352, 354, as well as the gapsbetween the rolls. These changes can be made to create customized leadpass bars 220 that result in customized threaded rebar 240 with littleto no longitudinal ribs 262 based on the individual requirements of eachcustomer, through an interchangeable and cost effective processutilizing standard rebar forming tooling and equipment.

In some embodiments as previously discussed above, instead of changingthe orientation of the lead pass bar in order to roll the lead pass barthrough the threaded pass roll set to form the threaded rebar, thethreaded pass roll set may be oriented 90 degrees with respect to thelead pass bar roll set. Alternatively, three or more rollers may beutilized instead of two rollers to form the threaded rebar product. Instill other embodiments, threads may be machined into the rebar.

It should be understood that “operatively coupled,” when used herein,means that the components may be formed integrally with each other, ormay be formed separately and coupled together. Furthermore, “operativelycoupled” means that the components may be formed directly to each other,or to each other with one or more components located between thecomponents that are operatively coupled together. Furthermore,“operatively coupled” may mean that the components are detachable fromeach other, or that they are permanently coupled together.

Although specific terms are employed herein, they are used in a genericand descriptive sense only and not for purposes of limitation. Inaddition, where possible, any terms expressed in the singular formherein are meant to also include the plural form and/or vice versa,unless explicitly stated otherwise. Accordingly, the terms “a” and/or“an” shall mean “one or more.”

Specific embodiments of the invention are described herein. Manymodifications and other embodiments of the invention set forth hereinwill come to mind to one skilled in the art to which the inventionpertains, having the benefit of the teachings presented in the foregoingdescriptions and the associated drawings. Therefore, it is to beunderstood that the invention is not to be limited to the specificembodiments disclosed and that modifications and other embodiments andcombinations of embodiments are intended to be included within the scopeof the appended claims. As such, it will be understood that, wherepossible, any of the advantages, features, functions, devices, and/oroperational aspects of any of the embodiments of the present inventiondescribed and/or contemplated herein may be included in any of the otherembodiments of the present invention described and/or contemplatedherein, and/or vice versa.

What is claimed is:
 1. A threaded rebar hoop, the threaded rebar hoopcomprising: a threaded rebar having a first end and a second end,wherein the threaded rebar is formed from a rolling process, wherein thethreaded rebar is bent into a hoop shape, and wherein the threaded rebaris void of longitudinal ribs along at least the first end and the secondend of the threaded rebar; and a coupling operatively coupling the firstend and the second end of the threaded rebar to form the threaded rebarhoop.
 2. The threaded rebar hoop of claim 1, further comprising: a stopoperatively coupled to the coupling, the first end of the threadedrebar, or the second end of the threaded rebar.
 3. The threaded rebarhoop of claim 2, wherein the coupling comprises a stop aperture, whereinthe stop is operatively coupled to the stop aperture to reduce orprevent rotation of the coupling on the first end or the second end ofthe threaded rebar.
 4. The threaded rebar hoop of claim 1, wherein thecoupling comprises an alignment feature, wherein the alignment featureis configured for aligning the first end and the second end within thecoupling using the alignment feature.
 5. The method of claim 3, whereina first coupling end on the first end of the threaded rebar hoop is atleast approximately the same length at the second coupling end on thesecond end of the threaded rebar hoop.
 6. The threaded rebar hoop ofclaim 1, wherein the first end or the second end has at least a straightportion on which the coupling is operatively coupled.
 7. The threadedrebar hoop of claim 1, wherein the threaded rebar is formed withoutlongitudinal ribs directly from the hot rolling process.
 8. The threadedrebar hoop of claim 7, wherein the hot rolling process comprises:providing a lead pass bar comprising a body extending along alongitudinal axis, wherein at least one portion of the body has across-section defining a plane that intersects the longitudinal axis,wherein a first part of the plane has a first width, a second part ofthe plane has a second width, and a third part of the plane has a thirdwidth, wherein the first width is less than the second width and thethird width, wherein the first part of the plane is located adjacent tothe longitudinal axis, and the second part of the plane and third partof the plane are located distal from the longitudinal axis on oppositeends of the first part of the plane, wherein the lead pass bar has aX-axis through the first part of the plane, the second part of the planeand the third part of the plane, and a Y-axis through only the firstpart of the plane, and wherein the lead pass bar is formed in a firstorientation along the longitudinal axis of the lead pass bar in one ormore lead pass bar roll sets in which the X-axis is substantiallyparallel to and the Y-axis is substantially perpendicular to lead passrolls of the one or more lead pass bar roll sets; and forming thethreaded rebar having substantially continuous threads from the leadpass bar by hot rolling the lead pass bar in one or more threaded rebarroll sets, wherein forming the threaded rebar comprises forming thethreaded rebar from the lead pass bar in a second orientation along thelongitudinal axis that is different from the first orientation in whichthe X axis is substantially perpendicular to and the Y-axis issubstantially parallel to threaded rolls of the one or more threadedrebar roll sets, and wherein the threaded rebar is formed without havingto remove longitudinal ribs along at least a portion of the body.
 9. Thethreaded rebar hoop of claim 1, wherein the threaded rebar hoop isformed in a shape of a circular hoop, a square hoop, a rectangular hoop,an oval hoop, or a triangular hoop.
 10. The threaded rebar hoop of claim1, wherein the threaded rebar is formed from two or more threaded rebarsections having at least one bend and two or more couplings, each of thetwo or more sections having the first end and the second end, whereinthe first end of each section is operatively coupled the second end ofeach adjacent section through the coupling from the two or morecouplings.
 11. The threaded rebar hoop of claim 1, wherein the rebar hassubstantially continuous threads.
 12. A method of forming a threadedrebar hoop, the method comprising: forming a threaded rebar from arolling process; bending the threaded rebar, wherein the threaded rebarhas a first end and a second end; threading a coupling onto the firstend of the threaded rebar hoop; drawing the second end of the threadedrebar hoop adjacent to the first end of the threaded rebar hoop; andthreading the coupling on the second end of the threaded rebar hoop. 13.The method of claim 12, further comprising: operatively coupling a stopto the coupling, the first end of the threaded rebar, or the second endof the threaded rebar.
 14. The method of claim 12, wherein the couplingcomprises a stop aperture, wherein the method further comprising:operatively coupling the stop within the stop aperture to reduce orprevent rotation of the coupling on the first end or the second end ofthe threaded rebar.
 15. The method of claim 12, wherein the rebar hoopcomprises an alignment feature, wherein the method further comprising:aligning the first end and the second end within the coupling using thealignment feature.
 16. The method of claim 12, wherein threading thecoupling on the second end of the threaded rebar hoop comprisesthreading the coupling until a first coupling end on the first end ofthe threaded rebar hoop is at least approximately the same length at thesecond coupling end on the second end of the threaded rebar hoop. 17.The method of claim 12, wherein the threaded rebar is formed withoutlongitudinal ribs directly from the hot rolling process.
 18. The methodof claim 12, wherein the threaded rebar is formed from two or morethreaded rebar sections having at least one bend and two or morecouplings, each of the two or more sections having the first end and thesecond end, wherein the first end of each section is operatively coupledthe second end of each adjacent section through the coupling from thetwo or more couplings.
 19. The method of claim 12, wherein the rebar hassubstantially continuous threads.
 20. The method of claim 12, whereinforming the threaded rebar comprises: providing a lead pass barcomprising a body extending along a longitudinal axis, wherein at leastone portion of the body has a cross-section defining a plane thatintersects the longitudinal axis, wherein a first part of the plane hasa first width, a second part of the plane has a second width, and athird part of the plane has a third width, wherein the first width isless than the second width and the third width, wherein the first partof the plane is located adjacent to the longitudinal axis, and thesecond part of the plane and third part of the plane are located distalfrom the longitudinal axis on opposite ends of the first part of theplane, wherein the lead pass bar has a X-axis through the first part ofthe plane, the second part of the plane and the third part of the plane,and a Y-axis through only the first part of the plane, and wherein thelead pass bar is formed in a first orientation along the longitudinalaxis of the lead pass bar in one or more lead pass bar roll sets inwhich the X-axis is substantially parallel to and the Y-axis issubstantially perpendicular to lead pass rolls of the one or more leadpass bar roll sets; and forming the threaded rebar having substantiallycontinuous threads from the lead pass bar by hot rolling the lead passbar in one or more threaded rebar roll sets, wherein forming thethreaded rebar comprises forming the threaded rebar from the lead passbar in a second orientation along the longitudinal axis that isdifferent from the first orientation in which the X axis issubstantially perpendicular to and the Y-axis is substantially parallelto threaded rolls of the one or more threaded rebar roll sets, andwherein the threaded rebar is formed without having to removelongitudinal ribs along at least a portion of the body.